The name Tohoshinki means "The Rising Gods of the East" and for five males (Jejung, Yuchun, Yunho, Changmin, and Junsu), this wasn't just any old name it was a title, a goal to be the top artists in Asia. Debuting in Korea on December 24, 2003, they quickly became a popular teenage chorus group in their homeland. By the date of their Japanese debut in 2005, Tohoshinki had not only made themselves known in Korea as a dance only boyband, but a quintet that had the ability to harmonize, vocalize, and dance to perfection; earning them many praises by many other Korean artists that they would refer to as sunbae-nim(korean for senpai).
With major success in Korea, Tohoshinki made their way to Japan, eager to conquer a foreign land. With that thought in mind, Tohoshinki decided that they did not want to come to Japan as Hallyu stars but as Japanese Pop idols and so their struggle began. For the first few months of their Japanese career, which had started with the release of the single: "Stay With Me Tonight", the members of Tohoshinki spent that time learning/improving their Japanese, battling the depression they got from both homesickness and not achieving the response they wanted immediately, language barriers, and thoughts of giving up completely in turn to go home. While promoting Purple Line in Korea, the members stated that they at first didn't want to work in Japan and were forced rather than having that motivation to work hard.

After months of hard work and intense Japanese studies, Tohoshinki finally got the break they were looking for with their second single, "Somebody To Love", which ranked at number fourteen on the Oricon chart and included their first ballad song. In November, Tohoshinki released "My Destiny", their first ballad single and with this single earned them the popularity they wanted. After "My Destiny" was released and sold more than any of their other singles, as well the gain of more fans, they released "Asu wa Kuru Kara" (can also romanized as "Ashita wa Kuru Kara"). With the release of "Asu wa Kuru Kara", that song became an instant success and was used as the seventeenth ending for the popular anime, ONE PIECE and soon the release of their final single for their first album, "Rising Sun/Heart, Mind and Soul" had arrived. Although the "Rising Sun/Heart, Mind and Soul" single hadn't done as well as the other singles, their first album, "Heart, Mind and Soul", was still a huge hit. Things had finally started to look up for the five members known as Tohoshinki and after the release of their album in 2006, they held their first nationwide tour: 1st Live Tour 2006: Heart, Mind and Soul. Tickets to 1st Live Tour 2006: Heart, Mind and Soul were sold out immediately.
With the success of their first five singles and their first album, they began working harder on their sixth single. In June, they released "Begin", a sweet, ballad song with an upbeat B-side("High Time") and they also appeared in the Avex summer festival A-Nation '06 that July and August. Their next and seventh single, "Sky", ranked number six on the Oricon chart making it their first single to be ranked in the Top Ten and at that time, the highest ranking single of their Japanese career. Three months later, Tohoshinki returned with yet another single, "miss you/"O"- 正・反・合" and this single ranked number three on the Oricon charts and was the first of many to come to be ranked in the Top Five as well as, replaced "Sky" as their highest ranking single. Somehow, they managed to hold conerts in Thailand, Malaysia, and China, earning them more fans and success. While their popularity was slowly, but surely growing in Japan, Tohoshinki's popularity in Korea rose even more(if that was possible) and in turn they earned lots of awards, these awards included: MKMF's Best Music Video for "순수"(Rising Sun), MKMF's People's Choice Award, MKMF's Artist of the Year, China-Ten Most Popular Music Group, China-Ten Most Popular Song, etc. . . After their second tour The 2nd Asia Tour Concert 'O' and with their increasing popularity in Japan, Tohoshinki released "Step by Step" and "Choosey Lover" both that were ranked in the top ten among cvery popular artists ("Step by Step" ranked number seven and "Choosey Lover" ranked number nine), not to mention that " Choosey Lover" was the opening theme song for Xenos Xenos. Finally recognized as Japanese Pop idols, they released their second album titled "Five in the Black" (ranked number ten on the Oricon charts) and held yet another nationwide concert to support this album. As they sang their song "Proud", Junsu and Yuchun broke out into tears, finally happy that they achieved their dream of breaking through in foreign territory and getting as far as they had.

In May of 2007, Tohoshinki attended the MTV Japan Music Awards and won the award "Best Buzz Asia in Korea" for their "'O'-正.反.合." album. From June to December of 2007, Tohoshinki released a string of five singles: "Lovin' You", "Summer: Summer Dream/Song for You/Love in the Ice", "Shine / Ride On", "Forever Love" and "Together". "Summer: Summer Dream/Song for You/Love in the Ice" peaked at number two on the Oricon charts, marking that single as their highest ranking single of the time. In November of 2007, Tohoshinki collaborated with Koda Kumi to create "LAST ANGEL", which peaked at number two and was the image song for the movie "Resident Evil: Extinction".
2008 marked the start of Tohoshinki's supreme rise in Japan. First in January, they released "Purple Line", marking that as not only their first single to peak at number one on the Oricon charts, but the first single to be produced by a non-Japanese band to peak at number one as well as the start of their reign as number one on the Oricon charts and their first single to be created by a non-Japanese staff. Before their amazing reign atop the Oricon charts could begin to rise, they released their third Japanese studio album titled "T" as well as indivdual singles that spelt out T.R.I.C.K (T: Two Hearts/WILD SOUL - Changmin, R: Runaway/MY GIRLFRIEND - Yuchun, I: If...?!/RAINY NIGHT - Junsu, C: Close to You/CRAZY LIFE - Yunho, K: Keyword/MAZE - Jejung). Following the release of the T.R.I.C.K singles, Tohoshinki released "Beautiful You / Sennen Koi Uta" in April, their second single to peak number one on the Oricon charts and the single that broke the twenty four year old record set by Ou-Yang Fei Fei (two singles to peak number one on the charts by a foreign artist). After "Beautiful You / Sennen Koi Uta", Tohoshinki returned to Korea for the 14th Annual Dream Concert on June 7th. Immediately following that concert, they wrapped their Asia tour in Beijing. Returning back to Japan, they released "どうして君を好きになってしまったんだろう？", their third single to peak at number one the Oricon charts and the single that made them the first non-Japanese artist to have three consecutive singles peak at number one. Following that release, they performed at Avex Trax's 20th Anniversary meeting and A-Nation '08. In August of 2008, Tohoshinki returned back to Korea to take part in SMTown '08 alongside BoA, Cheon Sang Ji Hee the Grace, Zhang Liyin, Girls' Generation, Shinee and Super Junior.
They released the fourth Korean studio album titled "Mirotic", another chart topping Korean album with 502,837 copies sold and earning them another record for the first Korean album in six years to sell more than 500,000 copies. In October, Tohoshinki returned to the Japanese Pop scene with "呪文: Mirotic", the Japanese counterpart of the title single to their fourth Korean album. "呪文: Mirotic" peaked number one, causing Tohoshinki to destroy their previous record with four single to peak number one. Tohoshinki then attended Kouhaku Uta Gassen Music Festival on New Year's Eve, making them the first Korean group to attend.
Tohoshinki's twenty-fifth single, "Bolero/Kiss the Baby Sky/忘れないで", released on January 21, 2009 was yet another single that peaked number one atop the Oricon charts, making them the first foreign artist to have five consecutive number one singles. In March, they released "Survivor", this single peaked at number three and subsequently ended their amazing number one reign. "Survivor" was succeeded by the release of their fourth Japanese studio album, "The Secret Code", which debuted at number two on the charts and thus, they embarked on their fourth live tour: Tohoshinki 4th Live Tour 2009: The Secret Code to help support the album. Tohoshinki 4th Live Tour 2009: The Secret Code ended in the Tokyo Dome, making them the first Korean group to perform on that stage. In April, they released "Share the World/ウィーアー!", another one of their singles that peaked number one and extended their record to six number one singles(not consecutive). In July, they released "Stand By U" and debuted at number two on the charts. On September 30, 2009, Jejung and Yuchun came together to produce the single "Colors: Melody and Harmony/Shelter". "Colors: Melody and Harmony" was composed and written by Yuchun and Jejung, while "Shelter" was also composed and written by Yuchun and Jejung with the help of Junsu. "Colors: Melody and Harmony/Shelter" debuted at number one and therefore making Tohoshinki the first non-Japanese artists to have seven singles top the Oricon charts. As of November 7, 2009, Tohoshinki has released yet another single, "Toki wo Tomete", a slow ballad song that was originally featured in a CF for the cosmetics brand Menard as well as TOHOSHINKI THE LIVE 2009.